Presentation imaging system

ABSTRACT

A presentation imaging system used for imaging machine readable information on an object is provided. The system includes a proximity sensor and an imaging device coupled to a processor. The sensor senses the presence of an object within a field of view. A light source projects a structured beam at a first intensity to define an imaging area generally co-extensive with the field of view. Upon detection of the object, the processor signals the light source to project the beam at a second, higher intensity for imaging.

BACKGROUND

[0001] The present application relates generally to an optical imagingsystem. More particularly, the invention provides a presentation imagingsystem for imaging and processing machine readable information on anobject which is carried thereunder and which provides a visual indicatorto an operator as to the imaging area and provides feedback to theoperator when the machine readable information has been imaged andsuccessfully processed.

[0002] Package monitoring capability is a vital task of modem inventorycontrol. In many warehousing and trunk loading facilities, packages arescanned as they are loaded onto or received from trucks or othershipping means. To aid in this task, scanners have been developed.Typically, two types of scanners are used, hand-held mobile scanners andnon-mobile linear scanners. Often, however, these two types of scannershave inherent limitations which affect their overall efficiency andusefulness.

[0003] Hand-held mobile scanners are used by operators to recordinformation contained on bar code labels. These scanners come in variousforms including wand, CCD, CMOS and portable laser scanners. Thesensitivity of these scanners requires them to be in close proximity tothe bar code to successfully read it. This direct contact/closeproximity reading requires slow package movement along the materialtransit path to allow handlers to scan the package without errors,ultimately increasing package handling costs. An additional problem withthese scanners is that they are limited in their usefulness. Thesescanners can only read bar code information and will not image an objectbased upon other characteristics.

[0004] Non-mobile linear scanning systems require precise alignmentbetween a bar code and the scanning system. In these systems, anoperator must locate a bar code on a package and then manipulate thepackage so that the bar code is in one of the required alignments forreading. These scanners have a greater scanning depth capabilityrelative to hand-held scanners. However, these scanners do not allowimaging of whole surfaces of packages at one time, rather they scan oneor more discrete lines while the package moves through a scanning area.

[0005] There is a need to provide an imaging system which will imageobjects from a remote point over a wide optical field or area whileallowing accurate reading of bar codes or other machine readableinformation located on a surface of the object. There is a further needto provide a system which will require minimal package manipulation inorder to accurately image an object and process the machine readableinformation, such that a user carrying an object can easily pass itthrough a defined imaging field as he loads or unloads the object. Thereis a still further need to provide a system for reading and processingmachine readable information on an object that is safe and providesconfirmation that successful processing of the information has occurred.

SUMMARY

[0006] The current invention provides a presentation imaging system usedfor reading and processing machine readable information on an object.The presentation imaging system comprises a sensor coupled to aprocessor, with the sensor being adapted to detect the presence of anobject within a field of view. An imaging device is coupled to theprocessor for imaging a surface of the object. A light source projects astructured beam at a first intensity to define an imaging area generallyco-extensive with the field of view. Upon detection of the object, theprocessor signals the light source to project the beam at a second,higher intensity for imaging.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The foregoing summary as well as the following detaileddescription of the preferred embodiments of the invention will be betterunderstood when read in conjunction with the appended drawings. For thepurpose of illustrating the invention, a presently preferred embodimentis shown. It should be understood, however, that the invention is notlimited to the precise arrangements shown. In the drawings:

[0008]FIG. 1 is schematic view of a presentation imaging system inaccordance with the preferred embodiment of the invention;

[0009]FIG. 2 is a view taken along line 2-2 in FIG. 1 which illustratesthe positioning of the sensor and observation axes of the imaging area.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The ensuing detailed description provides preferred exemplaryembodiments only, and is not intended to limit the scope, applicability,or configuration of the invention. Rather, the ensuing detaileddescription of the preferred exemplary embodiment(s) will provide thoseskilled in the art with an enabling description for implementing apreferred exemplary embodiment of the invention. It will be understoodby those skilled in the art that various changes may be made in thefunction and arrangement of elements without departing from the spiritand scope of the invention.

[0011] The current invention provides a presentation imaging system 10used to identify objects, such as packages. The system 10 is used toread machine readable information, such as bar codes, located on thesurface of an object.

[0012] Referring to FIG. 1, the system 10 is comprised of a processor 12connected to a sensor 14 and an imaging device 16. The imaging device 16receives images of objects located along an observation axis 54. Theimaging device 16 is preferably an area scan camera, including an areaarray sensor, or another similar device. The sensor 14 is preferably aproximity sensor or other similar device that can detect the presenceand/or the distance of an object. The processor 12 is coupled to thesensor 14 through a sensor connection 34.

[0013] As shown in FIG. 1, the imaging device 16 preferably has anattached lens 18. The attached lens 18 may be either a fixed focus orauto focus type which is driven by commands from the processor 12, basedon distance or position data received from the sensor 14. The automaticfocus lens may be controlled by any combination of the sensor 14, theimaging device 16, and/or the processor 12. For a fixed focus lens, thesensor 14 is used only to detect the presence of the object. To transferimages or image data, the imaging device 16 is coupled to the processor12 through a video connection 36.

[0014] The processor 12 captures the images obtained from the imagingdevice 16. Once the processor 12 captures the image, it processes theimage looking for coded symbologies or other preprogrammed machinereadable images or information. The processor 12 may be capable ofreading different bar code information. This bar code information mayinclude, but not be limited to, UPC, EAN, Codabar, I205, Code 39, Code128 and/or Code 93. Additionally, the imaging device 16 and theprocessor 12 may be capable of performing low, medium, or high densityimaging as required by the information on the objects to be scanned.Furthermore, the imaging device 16 and the processor 12 may be used foroptical character recognition (OCR) or recognition of 2d symbologies. Inthe preferred embodiment, the system 10 has the capability ofsuccessfully imaging objects placed at a distance in excess of 5 feetfrom the housing opening 28.

[0015] A light source 20 is connected to the processor 12 through alight source connection 46. The light source 20 is preferably a highintensity unit capable of providing a structured light beam 56 ofsufficient lumens to an object placed at a distance from the imagingdevice 16. Such light sources include, but are not limited to, halogen,xenon metal halide, or other lamp units. In the preferred embodiment,the light source 20 has at least two modes of operation controlled bythe processor 12. The first mode provides a low intensity illuminationto clearly define an imaging area which can be easily recognized bymaterial handlers, without a continuous high brightness that can obscurean operator's vision due to reflection from the package surface. Thisalso allows for lower power consumption for the majority of theoperating time for the system 10. In the second mode of operation, whichis preferably triggered when the sensor 14 detects the presence of theobject 44, the light source 20 brightly illuminates the object 44 placedin an imaging area 40, which is generally co-extensive with thestructured light 56 as shown in FIG. 2, allowing the camera 16 to imageany machine readable information on the object 44. The image passesthrough the lens 18 to the camera 16, where it is converted to an imagesignal that is transmitted via cable 36 to the processor 12, where it isprocessed looking for any preprogrammed machine readable information.Preferably, a third mode is provided that gives a visual acknowledgmentto the operator that the machine readable information on the object hasbeen processed. This can be through having the light source 20 turn offor blink before returning to the first mode. Alternatively, other typesof operator acknowledgment can be provided, such as an audio signalAdditionally, different colors of lights may be used between settings tomore clearly highlight the intensity settings used. Those skilled in theart will recognize that the number and intensity of the settings may bevaried.

[0016] A reflector 22 is preferably used to allow light generated by thelight source 20 to be reflected along the observational axis 54, asshown in FIG. 1. The reflector 22 reflects light generated by the lightsource 20 through a preferred angle of 45° relative to the observationaxis 54 in order to make the light from the light source 20 co-axialwith the observation axis 54. As those skilled in the art willrecognize, the positioning of the light source 20 and the reflector 22may be altered to provide differing configurations. Additionally, thelight source 20 may be a point source or any other type of source, andthe reflector 22 could be shaped to focus the light source to producethe structured beam 56. The reflector 22 is preferably a mirror,however, other embodiments may include other similar devices. In thepreferred embodiment, the reflector 22 has two openings 24, 26. A sensoropening 26 is created to allow the sensor 14 to send and receive signalsdown a sensor sight line 52. In a likewise manner, an imaging deviceopening 24 is provided to allow the imaging device 16 to obtain imagesthrough the reflector 22. Those skilled in the art will recognize thatthe cut-outs 24 and 26, may be of any size and geometry.

[0017] A housing 30 is provided to allow the components described aboveto be securely housed. Preferably, the presentation imaging system 10 isattached to a structural member in an overhead position allowing anunimpeded package imaging view. A housing window or opening 28 allowsthe sensor sight line 52, the imaging device field of view along theobservation axis 54, as well as the structured light beam 56 to exit thehousing 30.

[0018] Referring to FIGS. 1 and 2, the presentation imaging system 10 isshown imaging an object 44. The object 44 is moved into a positionwithin the imaging area 40 which can be easily recognized by the userbased on the structured beam 56 from the light source 20 illuminatingthe object 44. The sensor 14 detects the distance to the surface of theobject 44 along the sensor sight line 52, preferably using a signalreflected back from the surface of the object 44 when the object movesinto the sight line 52. In the preferred embodiment, the sight line 52and the observation axis 54 are in close proximity or nearly co-incidentwithin the scan range 38. As one skilled in the art will recognize,other configurations are possible including providing additional sensorsto cover additional sections of the imaging area. The imaging area 40 ofthe imaging system 10 may be altered based upon the needs of the userand the configuration of the imaging device, but is preferably coaxialand generally co-extensive with the structured light beam 56, as shownin FIG. 2.

[0019] The sensor 14 transmits distance data to the processor 12. Uponreceipt of the data, the processor 12 processes the data, provides focusinformation to the lens 18 of the camera 16, and intensifies the lightsource 20 to allow sufficient illumination of the object 44 for imaging.A feed back loop can also be programmed for distance data from thesensor 14 and the camera focusing to ensure that focusing is completedprior to imaging. The imaging device 16 is then activated by theprocessor 12. Reflected light from the surface of the object 44 isgathered by the imaging device 16 focused through the lens 18. Theimaging device 16 then transmits the image data to the processor 12. Theprocessor 12 processes the transmitted image and analyzes the dataagainst preprogrammed processing requirements. If the image issuccessfully verified, (for example, a bar code is read) the processor12 will provide the data to a predetermined destination, such as a hostcomputer system, and will provide notification that a successful scanhas been accomplished. As those skilled in the art will recognize thisnotification may include, but not be limited to, an audible alarm,winking the light source 20 off and on, changing the color of the lightsource 20 or other means.

[0020] While the operation of the preferred embodiment of the inventionhas been described in terms of an auto focus lens on the imaging device16, those skilled in the art will recognize from the present disclosurethat other options are available for providing imaging over a largedepth of field without the need for physically adjusting the focus of alens. This includes the possibility of using a cubic phase mask filterwhich provides for focus over a large depth of field, the use of brightlighting with a small aperture, as well as other non-moving partsolutions for focusing over a large depth of field. These arrangementshave the added benefit of no moving parts, which are generally thehighest wear/maintenance items.

[0021] While the preferred embodiment of the invention has beendescribed in detail, the invention is not limited to the specificembodiment described above, which should be considered as merelyexemplary. Further modifications and extensions of the present inventionmay be developed, and all such modifications are deemed to be within thescope of the present invention as defined by the appended claims.

What is claimed is:
 1. A presentation imaging system for imaging machinereadable information on an object, comprising: a processor; a sensorcoupled to the processor and adapted to detect the presence of an objectwithin a field of view; an imaging device coupled to the processor forimaging the object; and a light source which projects a structured beamat a first intensity to define an imaging area generally co-extensivewith the field of view connected to the processor and, upon detection ofthe object, the processor signals the light source to project thestructured beam at a second, higher intensity.
 2. The presentationimaging system of claim 1, wherein the light source has first, secondand third operating modes, the first operating mode being the firstintensity that has a low power consumption, the second operating modebeing the second, higher intensity for imaging the object, and the thirdoperating mode being an operator acknowledgment mode wherein theprocessor at least one of changes an intensity and blinks the lightsource off.
 3. The presentation imaging system of claim 2, wherein thelight intensity settings are controlled by the processor.
 4. Thepresentation imaging system of claim 1, wherein the imaging device is acamera with a focusable lens which receives focusing data from theprocessor based on object distance data provided by the sensor.
 5. Thepresentation imaging system of claim 1, wherein the sensor is aproximity sensor.
 6. The presentation imaging system of claim 1, whereina second color light signals notification of successful imaging of themachine readable information on the object.
 7. The presentation imagingsystem of claim 1, further comprising an audible or visual signalgenerator connected to the processor which activates upon successfulimaging of the machine readable information on the object.
 8. Thepresentation imaging system of claim 1, further comprising a reflectorhaving at least a first opening and a second opening, the first openingproviding a path for the imaging device to receive images through thereflector and the second opening providing a path for the sensor todetect the object.
 9. The presentation imaging system of claim 8,wherein the reflector is a mirror positioned at an angle of about 45° tothe axis.
 10. The presentation imaging system of claim 1, furthercomprising a housing, surrounding the processor, the sensor, the imagingdevice, and the light source, the housing having a window positionedbelow the imaging device.
 11. A method of imaging an object foridentification of machine readable information located thereon,comprising providing an imaging system which includes a processor, asensor coupled to the processor for detecting the presence of an objectwithin a field of view, an imaging device coupled to the processor forimaging the object, and a light source which projects a structured beamat a first intensity to define an imaging area generally co-extensivewith the field of view; a user visually identifying the imaging area bythe structured light beam and carrying the object to be processed intothe field of view; determining the presence of the object with thesensor; projecting the structured light beam at a second, higherintensity; imaging the object with the imaging device; analyzing imagedata for machine readable information with the processor; and loweringthe intensity of the structured light beam.
 12. The method of claim 11,wherein the machine readable information is a bar code.